bsnes/nall/range.hpp

52 lines
1.5 KiB
C++
Executable File

#pragma once
namespace nall {
struct range_t {
struct iterator {
iterator(int64_t position, int64_t step = 0) : position(position), step(step) {}
auto operator*() const -> int64_t { return position; }
auto operator!=(const iterator& source) const -> bool { return step > 0 ? position < source.position : position > source.position; }
auto operator++() -> iterator& { position += step; return *this; }
private:
int64_t position;
const int64_t step;
};
struct reverse_iterator {
reverse_iterator(int64_t position, int64_t step = 0) : position(position), step(step) {}
auto operator*() const -> int64_t { return position; }
auto operator!=(const reverse_iterator& source) const -> bool { return step > 0 ? position > source.position : position < source.position; }
auto operator++() -> reverse_iterator& { position -= step; return *this; }
private:
int64_t position;
const int64_t step;
};
auto begin() const -> iterator { return {origin, stride}; }
auto end() const -> iterator { return {target}; }
auto rbegin() const -> reverse_iterator { return {target - stride, stride}; }
auto rend() const -> reverse_iterator { return {origin - stride}; }
int64_t origin;
int64_t target;
int64_t stride;
};
inline auto range(int64_t size) {
return range_t{0, size, 1};
}
inline auto range(int64_t offset, int64_t size) {
return range_t{offset, size, 1};
}
inline auto range(int64_t offset, int64_t size, int64_t step) {
return range_t{offset, size, step};
}
}